1. Field of the Invention
The present invention relates generally to a feed circuit design for connecting adjacent components, such as antenna elements, and more particularly to a feed circuit design having improved structure and support, for connecting adjacent components while utilizing a reduced number of parts.
2. Description of Related Art
Phased array antennas have seen an increase in range of applications in recent years in various commercial markets. With respect to the defense market, phased array antennas have seen an increase in application in, for example, communications and radar systems, among various other applications.
For example, a phased array antenna developed by the Raytheon company includes a plurality of transmit/receive integrated microwave module (TRIMM) plates or assemblies that are arranged adjacent to one another in an array assembly, and a plurality of radiating elements extending from each of the TRIMM assemblies. The TRIMM assemblies each include a column portion to which other components are attached. Electrical performance of a phased array antenna depends on various factors, for example, the orientation of the various features in the antenna as well as the arrangement and intercommunication between these various features. Such features and/or factors may therefore affect the effectiveness, stability, and/or optimization of certain performance characteristics of different antennas.
Among the features which contribute to the communication between adjacent TRIMM assemblies in the above phased array antennas are feed circuits. Generally, feed circuits are utilized because typically in such phased array antennas, adjacent TRIMM assemblies do not directly contact one another. Due to manufacturing tolerances and variations between different TRIMM assemblies, if components are stacked to contact one another, inconsistencies from TRIMM assembly to TRIMM assembly may cause imprecise positioning between radiating elements, adversely affecting electrical performance, thereby reducing the effectiveness of the antennas. Furthermore, in such array assemblies, as the number of TRIMM assemblies in the array increases, any TRIMM assembly inconsistencies may further cause additional deviations from the desired spacing between the radiating elements, as errors may be compounded based on the increased number of TRIMM assemblies, and performance degradation of the antennas as a whole may further be magnified. Therefore, TRIMM assemblies may be arranged with a certain amount of clearance between them, such that a desired precise spacing can be set based on positioning between the radiating elements, rather than between the TRIMM assemblies, so as to eliminate or reduce spacing inconsistencies that would otherwise be caused by the manufacturing variations.
Accordingly, feed circuits have been designed to be placed between adjacent TRIMM assemblies and to bridge the gaps and facilitate communication between the TRIMM assemblies, as well as between the radiating elements associated with the TRIMM assemblies. Since the spacing between the TRIMM assemblies is inconsistent due to the manufacturing variations, such feed circuits are generally made to be flexible so as to accommodate such spacing and positioning variations. As indicated above, manufacturing variations may be caused, for example, by the TRIMM assemblies not being flat and/or, for example, by spacing tolerances between TRIMM assemblies in an array assembly. As such, the feed circuits themselves may be more structurally weak than may be desirable, and may not be provided adequate support by the structure of the TRIMM assemblies. Further, while the radiating elements and the TRIMM assemblies of the phased array antennas, which contribute more significantly to establishment of more precise and effective electric fields of the antennas, have improved over time, feed circuits have seen relatively less development and improvement over the same time.